1. Field of the Invention
The present invention relates to a fuel cutoff valve which is mounted at an upper portion of a fuel tank to cut off a communication between an interior and an exterior of the fuel tank and more particularly to a passageway construction of the fuel cutoff valve to the exterior of the fuel tank.
2. Description of the Related Art
Conventionally, a technology described in JP-A-2007-92834 is known as a fuel cutoff valve of the type described above. A fuel cutoff valve is mounted at an upper portion of the fuel tank and includes a cylindrical casing main body having a connecting hole at an upper portion thereof, a float which is accommodated in a valve chamber in the casing and a cover which covers the upper portion of the housing main body to define a communication chamber and from which an exhaust port is projected to connect to a canister side. The connecting hole in the casing main body is opened or closed by raising or lowering the float not only to secure a ventilation of a fuel tank to an exterior thereof but also to prevent fuel in the fuel tank from flowing out of the fuel tank to the exterior.
The casing main body has a bottom member at a bottom thereof, and this bottom member supports the float and has an opening which is formed therein to introduce the fuel or fuel vapor in the fuel tank into the casing main body. Communication holes are formed in the bottom member to establish a communication with the casing and are formed between pedestals which support the float.
However, at the pedestals which interrupt the communication between the casing and the bottom member, fuel which flows into the bottom member from the inside of the fuel tank as a result of oscillation of the vehicle strikes surfaces of the pedestals which face the fuel tank, and the fuel so striking the pedestals flows into the valve chamber in the casing through the communication holes to flow out to the exterior which is the canister side through the connecting hole from time to time.